I completed a Ph.D. in mathematics at UKC in 1994. This essentially concerned the embedding of Riemannian manifolds
in spaces of compactly-supported distributions. (And here's my undergraduate
dissertation, "A Short Survey of Lens Spaces", some topology I found fascinating at the time.)

Immediately thereafter, I took a one-year Royal Society European
exchange fellowship at
Ghent University in Belgium.
At the conclusion of this, I had published
a few minor papers, but had also gradually become disillusioned with
academia (particularly with what I saw as the over-specialisation of
modern scientific research). Consequently, I left mathematics to pursue
other interests.

"God may not play dice with the Universe, but there's something
strange going on with the prime numbers!"

(This quote has been misattributed to Erdös himself for many years now.)

In the winter of 1998, having been occasionally contemplating
the mystery of the prime distribution for a while, I was struck by
an even more overwhelming
intuition about its ultimate nature. My wish to get to
the truth of this matter led me back into serious mathematical study,
and ultimately to the creation of the number
theory and physics archive website.